Anti-peeping module and anti-peeping display equipment comprising same

Abstract

The invention discloses a peep-proof module and peep-proof display equipment comprising the same. The peep-proof module comprises a peep-proof element, a driving circuit, a voltage adjusting circuit and a temperature sensor. The peep-proof element comprises a liquid crystal layer, a first peep-proof electrode layer and a second peep-proof electrode layer, wherein the liquid crystal layer is located between the first peep-proof electrode layer and the second peep-proof electrode layer. The temperature sensor is used for sensing an environment temperature. The voltage regulation circuit is coupled to the temperature sensor. The driving circuit is coupled to the voltage adjusting circuit and the peep-proof element. When the environment temperature is a first environment temperature and the peep-proof element is operated in a peep-proof mode, the driving circuit outputs a first driving voltage to the peep-proof element; when the ambient temperature is a second ambient temperature and the peep-proof element is operated in the peep-proof mode, the driving circuit outputs a second driving voltage to the peep-proof element, the first ambient temperature is greater than the second ambient temperature, and the absolute value of the first driving voltage is less than the absolute value of the second driving voltage.

Description

Technical Field

[0001] The present invention relates to a display device, and more particularly to an anti-peeping module and an anti-peeping display device including the same. Background Art

[0002] Currently, electronic devices such as mobile phones, tablets, electronic pens or automotive products are equipped with anti-peeping products to meet the needs of privacy or driving safety. Anti-peeping products can be divided into physical anti-peeping films and switchable external electronic anti-peeping films. The purpose of the anti-peeping film is to prevent people from clearly seeing the screen from a specific direction.

[0003] However, in a low-temperature environment, the response time of the electronic anti-peeping film will be affected. When the temperature is too low, the electronic anti-peeping film has the problem of ineffective anti-peeping effect. Summary of the Invention

[0004] The present invention relates to an anti-peeping module and an anti-peeping display device including the same, which can adjust the driving voltage required for the anti-peeping module according to the ambient temperature.

[0005] According to an aspect of the present invention, an anti-peeping module is provided, which includes an anti-peeping element, a driving circuit, a voltage adjustment circuit, and a temperature sensor. The anti-peeping element includes a liquid crystal layer, a first anti-peeping electrode layer, and a second anti-peeping electrode layer, wherein the liquid crystal layer is located between the first anti-peeping electrode layer and the second anti-peeping electrode layer. The temperature sensor is used to sense an ambient temperature. The voltage adjustment circuit is coupled to the temperature sensor. The driving circuit is coupled to the voltage adjustment circuit and the anti-peeping element. When the ambient temperature is a first ambient temperature and the anti-peeping element operates in an anti-peeping mode, the driving circuit outputs a first driving voltage to the anti-peeping element; when the ambient temperature is a second ambient temperature and the anti-peeping element operates in the anti-peeping mode, the driving circuit outputs a second driving voltage to the anti-peeping element, wherein the first ambient temperature is greater than the second ambient temperature, and the absolute value of the first driving voltage is less than the absolute value of the second driving voltage.

[0006] According to an aspect of the present invention, an anti-peeping display device is provided, which includes a display panel and the above anti-peeping module, wherein the anti-peeping element is located on the light-incident side or the light-emitting side of the display panel.

[0007] In order to have a better understanding of the above and other aspects of the present invention, the following specific embodiments are given and described in detail in conjunction with the accompanying drawings: Brief Description of the Drawings

[0008] Figure 1 is a block diagram of an anti-peeping module according to an embodiment of the present invention;

[0009] Figure 2It is a schematic cross-sectional view of an anti-peeping element according to an embodiment of the present invention;

[0010] Figure 3A It is a schematic diagram of an anti-peeping display device according to an embodiment of the present invention;

[0011] Figure 3B It is a schematic diagram of an anti-peeping display device according to another embodiment of the present invention;

[0012] Figure 4A It is a waveform diagram of the first driving voltage of an anti-peeping element according to an embodiment of the present invention;

[0013] Figure 4B It is a waveform diagram of the second driving voltage of an anti-peeping element according to an embodiment of the present invention;

[0014] Figure 5 It is a relationship diagram of the ambient temperature and the response time of the liquid crystal molecules of an anti-peeping element according to an embodiment of the present invention;

[0015] Figure 6A It is a schematic diagram of an anti-peeping element in the sharing mode when the ambient temperature is 25°C to 27°C according to an embodiment of the present invention;

[0016] Figure 6B It is a schematic diagram of an anti-peeping element in the anti-peeping mode when the ambient temperature is 25°C to 27°C according to an embodiment of the present invention;

[0017] Figure 7A It is a schematic diagram of an anti-peeping element in the sharing mode when the ambient temperature is -40°C according to an embodiment of the present invention;

[0018] Figure 7B It is a schematic diagram of the anti-peeping mode of an anti-peeping element failing when the ambient temperature is -40°C according to an embodiment of the present invention;

[0019] Figure 7C It is a schematic diagram of increasing the driving voltage to enable the anti-peeping mode of an anti-peeping element to operate normally when the ambient temperature is -40°C according to an embodiment of the present invention;

[0020] Figure 8 It is a schematic diagram of a driving circuit, a voltage adjustment circuit, and a temperature sensor according to an embodiment of the present invention;

[0021] Figure 9 It is a schematic diagram of the driving voltage at different temperatures according to an embodiment of the present invention;

[0022] Figure 10 It is a schematic diagram of a driving circuit, a voltage adjustment circuit, and a temperature sensor according to another embodiment of the present invention;

[0023] Among them, reference numerals:

[0024] 10: Anti-peep display device;

[0025] 100: Anti-peep module;

[0026] 106: Backlight module;

[0027] 108: Display panel;

[0028] 110: Anti-peep element;

[0029] 111: First substrate;

[0030] 112: First anti-peep electrode layer;

[0031] 113: First alignment layer;

[0032] 114: Liquid crystal layer;

[0033] 115: Second alignment layer;

[0034] 116: Second anti-peep electrode layer;

[0035] 117: Second substrate;

[0036] 118: Spacer;

[0037] 119: Frame adhesive;

[0038] 120: Driving circuit;

[0039] 130: Voltage adjustment circuit;

[0040] 131: Low-temperature compensation circuit;

[0041] 132: Current source;

[0042] 140: Temperature sensor;

[0043] CP: Comparator;

[0044] DV: Driving voltage;

[0045] DV1: First driving voltage;

[0046] DV2: Second driving voltage;

[0047] GND: Ground terminal;

[0048] IL: Incident light;

[0049] IN1: First input terminal;

[0050] IN2: Second input terminal;

[0051] LC: Liquid crystal molecules;

[0052] N1, N2, N3, FBP: Nodes;

[0053] R1, R2, R3: Resistors;

[0054] RN: Thermistor;

[0055] SG1, SG2: Control signals;

[0056] T: Period;

[0057] TA: Ambient temperature;

[0058] USR1, USR2, USR3: Users;

[0059] VA1: Viewing angle;

[0060] VA2: Viewing angle;

[0061] VDD: High potential terminal;

[0062] V H ’, V L ’, V H , V L : Voltage;

[0063] VFBP: Feedback voltage;

[0064] VR: Reference potential;

[0065] Vref: Current source;

[0066] X, Y, Z: Directions. Detailed implementation manner

[0067] Figure 1 is a block diagram of an anti-peeping module 100 according to an embodiment of the present invention, Figure 2 is a cross-sectional view of an anti-peeping element 110 according to an embodiment of the present invention. Figure 3A is a schematic diagram of an anti-peeping display device 10 according to an embodiment of the present invention. Figure 3B is a schematic diagram of an anti-peeping display device 10 according to another embodiment of the present invention. Please refer to Figure 1 , 2 , 3A, 3B. As Figure 1As shown, in one embodiment, the anti-peeping module 100 includes an anti-peeping element 110, a driving circuit 120, a voltage adjustment circuit 130, and a temperature sensor 140. In this embodiment, the anti-peeping module 100 can achieve the effect of anti-peeping by changing the viewing angle of the anti-peeping element 110 according to the needs of the user in different usage scenarios. For example, the anti-peeping element 110 can be switched between a sharing mode and an anti-peeping mode, wherein the viewing angle of the anti-peeping element 110 in the sharing mode is greater than the viewing angle of the anti-peeping element 110 in the anti-peeping mode. In this embodiment, the anti-peeping element 110 can also be called an anti-peeping panel or a viewing angle control panel.

[0068] like Figure 3A and 3B As shown, the anti-peeping display device 10 includes a display panel 108, an anti-peeping module 100 and a backlight module 106. It should be noted that Figure 3A and 3B Only the privacy protection element 110 in the privacy protection module 100 is shown, and the privacy protection elements 110 and 111 are omitted. Figure 1 The drive circuit 120, the voltage adjustment circuit 130 and the temperature sensor 140 in the anti-peeping module 100. The display panel 108 is used to display the image, and the anti-peeping element 110 is used to adjust the viewing angle of the anti-peeping display device 10. When the anti-peeping element 110 is in the sharing mode, the anti-peeping display device 10 has a first viewing angle VA1; and when the anti-peeping element 110 is in the anti-peeping mode, the anti-peeping display device 10 has a second viewing angle VA2, wherein the second viewing angle VA2 is smaller than the first viewing angle VA1. Figure 3A As shown, the display panel 108 is located between the backlight module 106 and the peep-proof element 110, that is, the peep-proof element 110 is located on the light-emitting side of the display panel 108. Figure 3B As shown, the peep-proof element 110 is located between the backlight module 106 and the display panel 108, that is, the peep-proof element 110 is located on the light incident side of the display panel 108. Figure 3A and 3B In the embodiment of FIG. 1 , the display panel 108 may be a non-self-luminous display panel, such as a liquid crystal display panel. Figure 3A In a modified embodiment, the anti-peeping display device 10 may not include the backlight module 106, and the display panel 108 may be a self-luminous display panel, such as a light emitting diode display panel.

[0069] like Figure 2As shown, the anti-peeping element 110 includes a first substrate 111, a first anti-peeping electrode layer 112, a first alignment layer 113, a liquid crystal layer 114, a second alignment layer 115, a second anti-peeping electrode layer 116, a second substrate 117, spacers 118, and sealant 119, wherein the liquid crystal layer 114 includes a plurality of liquid crystal molecules (not shown in the figure). In some embodiments, the anti-peeping element 110 further includes at least one polarizer (not shown in the figure). For example, the anti-peeping element 110 may further include two polarizers, respectively located on the side of the first substrate 111 facing away from the liquid crystal layer 114 and on the side of the second substrate 117 facing away from the liquid crystal layer 114. The liquid crystal layer 114 is located between the first anti-peeping electrode layer 112 and the second anti-peeping electrode layer 116, the first alignment layer 113 is located between the first anti-peeping electrode layer 112 and the liquid crystal layer 114, the second alignment layer 115 is located between the second anti-peeping electrode layer 116 and the liquid crystal layer 114, the first anti-peeping electrode layer 112 is located between the first alignment layer 113 and the first substrate 111, and the second anti-peeping electrode layer 116 is located between the second alignment layer 115 and the second substrate 117. The first anti-peeping electrode layer 112 and the second anti-peeping electrode layer 116 are light-transmitting electrode layers, so that light can penetrate the anti-peeping element 110. The materials of the first anti-peeping electrode layer 112 and the second anti-peeping electrode layer 116 may be transparent conductive materials, such as but not limited to indium tin oxide or indium zinc oxide. The sealant 119 is used to bond the first substrate 111 and the second substrate 117, so that the liquid crystal layer 114 is located in the space formed by the first substrate 111, the second substrate 117, and the sealant 119, that is, the anti-peeping element 110 is a liquid crystal cell. The spacers 118 are located between the first substrate 111 and the second substrate 117, and are used to maintain the height of the gap (cell gap) of the liquid crystal cell.

[0070] The driving circuit 120 is electrically connected to the first anti-peeping electrode layer 112 and the second anti-peeping electrode layer 116 of the anti-peeping element 110, and is used to provide the driving voltage DV (or called the cross voltage of the liquid crystal layer 114, which is the voltage difference between the first anti-peeping electrode layer 112 and the second anti-peeping electrode layer 116) required by the anti-peeping element 110, so that the liquid crystal molecules in the liquid crystal layer 114 are rotated to a predetermined angle. When the anti-peeping element 110 is in the anti-peeping mode, the driving circuit 120 respectively provides a first voltage and a second voltage to the first anti-peeping electrode layer 112 and the second anti-peeping electrode layer 116. The difference between the first voltage and the second voltage (i.e., the voltage difference between the first voltage and the second voltage) is the driving voltage DV, and the driving voltage DV is not equal to 0. In addition, in the sharing mode, the driving voltage DV is equal to 0, or the driving voltage DV is not applied (at least one of the first anti-peeping electrode layer 112 and the second anti-peeping electrode layer 116 is floating). Therefore, the anti-peeping module 100 can change the rotation angle of the liquid crystal molecules through the driving voltage DV, so that the anti-peeping element 110 is switched between the anti-peeping mode and the sharing mode.

[0071] The voltage adjustment circuit 130 is electrically connected to the temperature sensor 140 and the driving circuit 120. The temperature sensor 140 is used to sense the ambient temperature, and when the ambient temperature changes, the voltage adjustment circuit 130 correspondingly adjusts the value of the driving voltage DV output by the driving circuit 120. Specifically, the temperature sensor 140 may include a temperature sensing element. When the ambient temperature changes, the characteristics of the temperature sensing element change (such as but not limited to the resistance, current, or voltage of the temperature sensing element changing), thereby enabling the temperature sensor 140 to measure the ambient temperature or the characteristics of the temperature sensor 140 to change corresponding to the change in the ambient temperature. And the voltage adjustment circuit 130 dynamically adjusts the value of the driving voltage DV output by the driving circuit 120 according to the ambient temperature measured by the temperature sensor 140 or the characteristic change of the temperature sensor 140, that is, when the ambient temperature changes, the voltage adjustment circuit 130 can compensate the driving voltage DV (that is, correspondingly adjust the value of the driving voltage DV at different ambient temperatures). In this embodiment, when the ambient temperature is the first ambient temperature and the anti-peeping element 110 operates in the anti-peeping mode, the driving circuit 120 outputs a first driving voltage to the anti-peeping element 110; when the ambient temperature is the second ambient temperature and the anti-peeping element 110 operates in the anti-peeping mode, the driving circuit 120 outputs a second driving voltage to the anti-peeping element 110, where the first ambient temperature is greater than the second ambient temperature, and the absolute value of the first driving voltage is less than the absolute value of the second driving voltage.

[0072] Figure 4A is the waveform diagram of the first driving voltage of the anti-peeping element 110 according to an embodiment of the present invention. Figure 4B is the waveform diagram of the second driving voltage of the anti-peeping element 110 according to an embodiment of the present invention. Please refer to Figure 2 、 4A 、4B. In this embodiment, the first and second driving voltages DV1, DV2 may be AC signals to avoid polarization of the liquid crystal molecules of the anti-peeping element 110. As Figure 4A shown, the first driving voltage DV1 of the anti-peeping element 110 is an AC signal (represented by a square wave), and the driving voltage DV1 is VH and VL respectively in a part and the rest of a cycle T of the AC signal (such as half of a cycle T and the other half), where VH is greater than 0V (volt), and VL is less than 0V. In this article, VH and VL may also be referred to as the first driving positive voltage and the first driving negative voltage respectively. As Figure 4B shown, the second driving voltage DV2 of the anti-peeping element 110 is VH' and VL' respectively in a part and the rest of a cycle T of the AC signal (such as half of a cycle T and the other half), where VH' is greater than 0V, and VL' is less than 0V. In this article, VH' and VL' may also be referred to as the second driving positive voltage and the second driving negative voltage respectively. Figure 4A and Figure 4BThe difference is that VH' is greater than VH, and VL' is less than VL, that is, the absolute value of the first driving voltage DV1 is less than the absolute value of the second driving voltage DV2. For example, VH and VL can be 4.76V and -4.76V respectively, and VH' and VL' can be 7.56V and -7.56V respectively. In Figure 4A and Figure 4B , within half of a period T of the AC signal and the other half, the first driving voltage DV1 (or the second driving voltage DV2) is VH and VL (or VH' and VL'), respectively, but it is not limited to this. The time ratios of VH and VL (or VH' and VL') within a period T can be adjusted according to requirements.

[0073] Figure 5 is a graph showing the relationship between the ambient temperature and the response time of the liquid crystal molecules of the anti-peeping element 110 according to an embodiment of the present invention. Please refer to Figure 5 . Figure 5 In, the horizontal axis represents the ambient temperature, and the vertical axis represents the response time of the liquid crystal molecules. Figure 5 In, the line segment of 65Hz represents the relationship between the ambient temperature and the response time of the liquid crystal molecules of the anti-peeping element 110 when the frequency of the driving voltage DV is 65Hz, and the line segment of 70Hz represents the relationship between the ambient temperature and the response time of the liquid crystal molecules of the anti-peeping element 110 when the frequency of the driving voltage DV is 70Hz. Figure 5 The label 4.76V in represents that the absolute value of the driving voltage DV in the range of the ambient temperature from 85°C to -35°C is 4.76V (for example, the driving voltage DV is the first driving voltage DV1 in Figure 4A ); and Figure 5 The label 7.56V in represents that when the ambient temperature is -40°C, the absolute value of the driving voltage DV is 7.56V (for example, the driving voltage DV is the second driving voltage DV2 in Figure 4B ). As Figure 5 shows, when the ambient temperature is lower than 25°C, the response time of the liquid crystal molecules begins to increase. Especially when the ambient temperature is in the range of -25°C to -35°C, the response time of the liquid crystal molecules increases sharply (by about 548%). Even when the ambient temperature is -40°C, the response time of the liquid crystal molecules cannot be measured. That is, when the ambient temperature drops, the liquid crystal phase of the liquid crystal layer 114 gradually tends to be solid (crystalline state), so the response time increases. Even when the ambient temperature is -40°C, the liquid crystal molecules of the anti-peeping element 110 turn abnormally, resulting in the failure of the anti-peeping mode of the anti-peeping element 110. Therefore, when the ambient temperature is -40°C, the absolute value of the driving voltage DV is increased to 7.56V, and the response time of the liquid crystal molecules decreases, making the anti-peeping mode of the anti-peeping element 110 normal.

[0074] Table 1 shows the measurement of luminance values and BR values at polar angle = 0° and azimuth angle = 270° when the anti-peeking element 110 is in the anti-peeking mode, at different ambient temperatures and driving voltages DV, where the frequency of the driving voltage DV is 70 Hz. Table 2 shows the measurement of luminance values and BR values at polar angle = 35° and azimuth angle = 270° when the anti-peeking element 110 is in the anti-peeking mode, at different ambient temperatures and driving voltages DV, where the frequency of the driving voltage DV is 70 Hz. The BR (Brightness Ratio) value in Table 1 is the ratio of the luminance measured at polar angle = 0° and azimuth angle = 270° in the anti-peeking mode to the luminance measured at polar angle = 0° and azimuth angle = 270° in the sharing mode, and the BR value in Table 2 is the ratio of the luminance measured at polar angle = 35° and azimuth angle = 270° in the anti-peeking mode to the luminance measured at polar angle = 35° and azimuth angle = 270° in the sharing mode. Please refer to Figure 2 , with the normal direction (i.e., direction Z) of the XY plane (the plane formed by direction X and direction Y) of the anti-peeking element 110 as the reference, the angle between the measurement direction of the luminance value and the BR value and the above normal line is the polar angle. Therefore, the luminance values and BR values measured at polar angle = 0° represent the luminance values and BR values measured from the front of the anti-peeking element 110, and the luminance values and BR values measured at polar angle = 35° represent the luminance values and BR values measured from the side of the anti-peeking element 110. As shown in Table 1, when the anti-peeking element 110 is in the anti-peeking mode and the ambient temperature drops to -40°C, the driving voltage DV needs to be increased to 7.1 V so that the luminance value and BR value of the front of the anti-peeking element 110 (i.e., polar angle = 0°) can be maintained at greater than 4900 and 99% respectively, that is, the front is visible. As shown in Table 2, when the anti-peeking element 110 is in the anti-peeking mode and the ambient temperature drops to -40°C, the driving voltage DV needs to be increased to 7.3 V so that the luminance value and BR value of the side of the anti-peeking element 110 (i.e., polar angle = 35°) can be reduced to less than 45 and 3.5% respectively, that is, the side is anti-peeking. In summary, when the ambient temperature drops to -40°C, the driving voltage DV is preferably greater than 7.3 V (e.g., 7.56 V) so that when the anti-peeking element 110 is in the anti-peeking mode, the front is visible and the side is anti-peeking.

[0075] Table 1

[0076]

[0077] Table 2

[0078]

[0079] Table 3 shows the absolute values of the driving voltages of the anti-peeping element 110 in the sharing mode and the anti-peeping mode at different ambient temperatures when the anti-peeping element 110 is in the anti-peeping mode. As shown in Table 3, when the anti-peeping element 110 is in the sharing mode, the absolute value of the driving voltage DV is 0V at ambient temperatures from 85°C to -40°C; when the anti-peeping element 110 is in the anti-peeping mode, the absolute value of the driving voltage DV is 4.76V at ambient temperatures from 85°C to -35°C, and the absolute value of the driving voltage DV increases to 7.56V at an ambient temperature of -40°C to prevent the anti-peeping mode of the anti-peeping element 110 from failing at low temperatures. In summary, when the anti-peeping element 110 is in the anti-peeping mode, the voltage adjustment circuit 130 can dynamically adjust the value of the driving voltage DV output by the driving circuit 120 at different ambient temperatures. When the ambient temperature is the first ambient temperature (for example, any temperature from 85°C to -35°C), the driving circuit 120 outputs the first driving voltage (for example, 4.76V); when the ambient temperature is the second ambient temperature (for example, -40°C), the driving circuit 120 outputs the second driving voltage (for example, 7.56V), where the first ambient temperature is greater than the second ambient temperature, and the absolute value of the first driving voltage is less than the absolute value of the second driving voltage.

[0080] Table 3

[0081] 85°C to -35°C -40℃ Sharing mode 0V 0V Anti-peeking mode 4.76V 7.56V

[0082] The above embodiments take the driving voltage of 4.76V at ambient temperatures from 85°C to -35°C and the driving voltage of 7.56V at an ambient temperature of -40°C as examples, but the present invention is not limited thereto. The temperature range for increasing the driving voltage DV and the adjustment ratio of the driving voltage DV can be designed according to the structural design of the anti-peeping element 110 and the characteristics of the liquid crystal molecules. For example, in some embodiments, when the anti-peeping element 110 is in the anti-peeping mode, the voltage adjustment circuit 130 can dynamically adjust the value of the driving voltage DV output by the driving circuit 120 at different ambient temperatures. When the ambient temperature is the first ambient temperature, the driving circuit 120 outputs the first driving voltage; when the ambient temperature is the second ambient temperature, the driving circuit 120 outputs the second driving voltage, where the first ambient temperature is, for example, greater than or equal to 0°C, the second ambient temperature is, for example, less than 0°C, and the absolute value of the second driving voltage can be 1.4 to 2 times the absolute value of the first driving voltage. For example, the absolute value of the first driving voltage can be 4 to 5V, and the absolute value of the second driving voltage can be 7 to 8V.

[0083] Figure 6A FIG. 13 is a schematic diagram showing the anti-peeping element 110 in the sharing mode when the ambient temperature TA is from 25°C to 27°C according to an embodiment of the present invention. Figure 6BIt is a schematic diagram of the anti-peeping element 110 in the anti-peeping mode when the ambient temperature is 25°C to 27°C according to an embodiment of the present invention. In Figure 6A , 6B and in the following Figure 7A , 7B , 7C, in order to simplify the drawing, the anti-peeping element 110 is only shown with the first anti-peeping electrode layer 112, the liquid crystal layer 114 and the second anti-peeping electrode layer 116, while the polarizer and Figure 2 the first substrate 111, the first alignment layer 113, the second alignment layer 115, the second substrate 117, the spacer 118 and the sealant 119 in Figure 6A are omitted. As Figure 6B shown, when the driving voltage DV is 0V, or at least one of the first anti-peeping electrode layer 112 and the second anti-peeping electrode layer 116 is floating, the anti-peeping element 110 is in the sharing mode, and at least most of the incident light IL on the incident side of the anti-peeping element 110 will penetrate the anti-peeping element 110 and be emitted from the front and side surfaces of the anti-peeping element 110, so that the user USR1 on the front surface of the anti-peeping element 110 and the users USR2, USR3 on the side surface of the anti-peeping element 110 can see the screen. As Figure 6B shown, when the driving voltage DV is 4.76V, the anti-peeping element 110 is in the anti-peeping mode, and the electric field between the first anti-peeping electrode layer 112 and the second anti-peeping electrode layer 116 will drive the liquid crystal molecules LC in the liquid crystal layer 114 to rotate and change the angle of the liquid crystal molecules LC. Therefore, when the incident light IL passes through the liquid crystal layer 114, it will be affected by the liquid crystal molecules LC and change the polarization state, so that a part of the incident light IL on the incident side of the anti-peeping element 110 will penetrate the anti-peeping element 110 and be emitted from the front surface of the anti-peeping element 110, and the brightness of the light emitted from the side surface of the anti-peeping element 110 becomes smaller, so that the user USR1 can see the screen, but the users USR2, USR3 cannot clearly see the screen. In Figure 6A , 6B and in the following Figure 7A , 7B , 7C, the incident light IL can be the image light of the display panel (for example, in the embodiment of Figure 3A the display panel 108 is located on the incident side of the anti-peeping element 110, and the image light of the display panel 108 is the incident light of the anti-peeping element 110) or the light of the backlight module (for example, in the embodiment of Figure 3B the backlight module 106 and the display panel 108 are respectively located on the incident side and the light-emitting side of the anti-peeping element 110, and the light generated by the backlight module 106 is the incident light of the anti-peeping element 110).

[0084] Figure 7A It is a schematic diagram of the anti-peeping element 110 in the sharing mode when the ambient temperature TA is -40°C according to an embodiment of the present invention. Figure 7BIt is a schematic diagram showing that the anti-peeping mode of the anti-peeping element 110 fails when the ambient temperature is -40°C according to an embodiment of the present invention. Figure 7C It is a schematic diagram showing that when the ambient temperature TA is -40°C according to an embodiment of the present invention, the driving voltage DV is increased to enable the anti-peeping mode of the anti-peeping element 110 to operate normally. As Figure 7A shown, when the driving voltage DV is 0V, the anti-peeping element 110 is in the sharing mode, and the users USR1, USR2, and USR3 can see the screen. As Figure 7B shown, when a driving voltage DV of 4.76V is applied to make the anti-peeping element 110 enter the anti-peeping mode, since the electric field between the first anti-peeping electrode layer 112 and the second anti-peeping electrode layer 116 fails to rotate the liquid crystal molecules LC, the anti-peeping mode of the anti-peeping element 110 fails, that is, the users USR1, USR2, and USR3 can still see the screen. As Figure 7C shown, therefore, the driving voltage DV is increased to 7.56V, and the electric field between the first anti-peeping electrode layer 112 and the second anti-peeping electrode layer 116 drives the liquid crystal molecules LC to rotate, so that the anti-peeping element 110 enters the anti-peeping mode, that is, the user USR1 can see the screen, but the users USR2 and USR3 cannot clearly see the screen.

[0085] Please refer to Figure 1 . The voltage adjustment circuit 130 is electrically connected to the temperature sensor 140 and the driving circuit 120. The temperature sensor 140 is used to sense the ambient temperature, and when the ambient temperature changes, the voltage adjustment circuit 130 correspondingly adjusts the value of the driving voltage DV output by the driving circuit 120. Specifically, the temperature sensor 140 may include a temperature sensing element. When the ambient temperature changes, the characteristics of the temperature sensing element change, and the voltage adjustment circuit 130 dynamically adjusts the value of the driving voltage DV output by the driving circuit 120 according to the ambient temperature measured by the temperature sensor 140 or the characteristic change of the temperature sensor 140. For example, the temperature sensing element of the temperature sensor 140 may include a thermistor, and when the temperature changes, the resistance value of the thermistor changes. The thermistor may be a negative temperature coefficient thermistor or a positive temperature coefficient thermistor. In an embodiment where the thermistor is a negative temperature coefficient thermistor, the lower the temperature, the higher the resistance value of the thermistor; and in an embodiment where the thermistor is a positive temperature coefficient thermistor, the lower the temperature, the lower the resistance value of the thermistor. Next, two embodiments will be used to illustrate that the voltage adjustment circuit 130 dynamically adjusts the value of the driving voltage DV output by the driving circuit 120 according to the characteristic change of the temperature sensor 140 corresponding to different ambient temperatures (such as the resistance value change of the temperature sensor 140 corresponding to different ambient temperatures).

[0086] Figure 8 It is a schematic diagram of the driving circuit 120, the voltage adjustment circuit 130, and the temperature sensor 140 according to an embodiment of the present invention.Figure 9 It is a schematic diagram of drive voltages at different temperatures according to an embodiment of the present invention. Please refer to Figure 1 and Figure 8 . The voltage adjustment circuit 130 includes a low-temperature compensation circuit 131, a current source 132, and resistors R1 and R2, and the temperature sensor 140 includes a thermistor RN, where the thermistor RN is a negative temperature coefficient thermistor. The resistor R2 and the thermistor RN are in parallel, where both ends of the resistor R2 are respectively coupled to the node N1 and the ground terminal GND, and both ends of the thermistor RN are respectively coupled to the node N1 and the ground terminal GND. Both ends of the resistor R1 are respectively coupled to the node N1 and the node N2. The current source 132 is coupled to the node N2, so that the current of the current source 132 can flow from the reference voltage Vref through the resistors R1, R2, and the thermistor RN to the ground terminal GND. Since the thermistor RN is a negative temperature coefficient thermistor, when the ambient temperature changes, the resistance value of the thermistor RN changes, thereby changing the voltage value of the node N2. The low-temperature compensation circuit 131 is coupled to the node N2 and the drive circuit 120, and the low-temperature compensation circuit 131 outputs a control signal SG1 to the drive circuit 120. The drive circuit 120 is coupled to the node FBP, and the voltage of the node FBP is the feedback voltage VFBP, which is a voltage division of the drive voltage DV. In this embodiment, when the temperature decreases, the voltage of the node N2 changes, the low-temperature compensation circuit 131 can change the control signal SG1 according to the voltage of the node N2, and the drive circuit 120 can change the feedback voltage VFBP according to the control signal SG1, thereby adjusting the drive voltage DV. Please refer to Figure 9 . When the ambient temperature is greater than or equal to TH, the drive voltage DV is VH; and when the ambient temperature is less than or equal to TL, the drive voltage DV is VH', where VH' is greater than VH. For example, the ambient temperature TL can be -40 °C, and VH and VH' can be 4.76 V and 7.56 V respectively.

[0087] Figure 10 It is a schematic diagram of the drive circuit 120, the voltage adjustment circuit 130, and the temperature sensor 140 according to another embodiment of the present invention. Please refer to Figure 1 and Figure 10The voltage adjustment circuit 130 includes a comparator CP and a resistor R3, and the temperature sensor 140 includes a thermistor RN. The resistor R3 and the thermistor RN are connected in series, where the two ends of the resistor R3 are respectively coupled to the node N3 and the ground terminal GND, and the two ends of the thermistor RN are respectively coupled to the node N3 and the high potential terminal VDD, where the potential of the high potential terminal VDD is greater than the potential of the ground terminal GND. In an embodiment where the thermistor RN is a positive temperature coefficient thermistor (i.e., the lower the temperature, the smaller the resistance value of the thermistor RN), when the temperature decreases, the potential of the node N3 will increase; while in an embodiment where the thermistor RN is a negative temperature coefficient thermistor (i.e., the lower the temperature, the greater the resistance value of the thermistor RN), when the temperature decreases, the potential of the node N3 will decrease. The node N3 is coupled to the first input terminal IN1 of the comparator CP, the second input terminal of the comparator CP receives a reference potential VR, and the comparator CP outputs a control signal SG2. In this embodiment, the first input terminal IN1 is a positive input terminal, and the second input terminal IN2 is a negative input terminal, where when the potential of the node N3 is greater than the reference potential VR, the control signal SG2 has a high potential; and when the potential of the node N3 is less than the reference potential VR, the control signal SG2 has a low potential. The driving circuit 120 receives the control signal SG2 and adjusts the output driving voltage DV according to the potential of the control signal SG2. For example, the circuit of the driving circuit 120 can be designed to output a first driving voltage when the control signal SG2 has a low potential, and output a second driving voltage when the control signal SG2 has a high potential, where the absolute value of the second driving voltage is greater than the absolute value of the first driving voltage; or the circuit of the driving circuit 120 can be designed to output a second driving voltage when the control signal SG2 has a low potential, and output a first driving voltage when the control signal SG2 has a high potential, where the absolute value of the second driving voltage is greater than the absolute value of the first driving voltage.

[0088] For example, in an embodiment where the thermistor RN is a positive temperature coefficient thermistor and the first ambient temperature is greater than the second ambient temperature, when the ambient temperature is the first ambient temperature, the potential of the node N3 may be less than the reference potential VR, the control signal SG2 has a low potential, and the driving circuit 120 outputs a first driving voltage according to the potential of the control signal SG2; when the ambient temperature is the second ambient temperature, the potential of the node N3 may be greater than the reference potential VR, the control signal SG2 has a high potential, and the driving circuit 120 outputs a second driving voltage according to the potential of the control signal SG2, where the absolute value of the second driving voltage is greater than the absolute value of the first driving voltage.

[0089] In an embodiment where the thermistor RN is a negative temperature coefficient thermistor and the first ambient temperature is greater than the second ambient temperature, when the ambient temperature is the first ambient temperature, the potential of node N3 can be greater than the reference potential VR, the control signal SG2 has a high potential, and the driving circuit 120 outputs a first driving voltage according to the potential of the control signal SG2; when the ambient temperature is the second ambient temperature, the potential of node N3 can be less than the reference potential VR, the control signal SG2 has a low potential, and the driving circuit 120 outputs a second driving voltage according to the potential of the control signal SG2, wherein the absolute value of the second driving voltage is greater than the absolute value of the first driving voltage.

[0090] In addition, in a modified embodiment, the positions of the resistor R3 and the thermistor RN in Figure 10 may also be exchanged, that is, the two ends of the thermistor RN are respectively coupled to the node N3 and the ground terminal GND, and the two ends of the resistor R3 are respectively coupled to the node N3 and the high potential terminal VDD. Similarly, when the ambient temperature changes, the potential of the node N3 can be changed, and further the potential of the control signal SG2 output by the comparator CP can be changed, and the driving circuit 120 adjusts the output driving voltage DV according to the potential of the control signal SG2.

[0091] In the above embodiments and modified embodiments, the ambient temperature at which the driving voltage DV changes can be determined by adjusting the resistance values of the resistor R3 and the thermistor RN and the potential value of the reference potential VR. For example, the anti-peeping module 100 can be designed such that the driving voltage DV increases from 4.76V to 7.56V at -40°C by adjusting the resistance values of the resistor R3 and the thermistor RN and the potential value of the reference potential VR.

[0092] The anti-peeping module of the above embodiments of the present invention and the anti-peeping display device including the same can achieve the anti-peeping effect by changing the viewing angle according to the privacy requirements of the user in different usage scenarios. In addition, the anti-peeping module can improve the anti-peeping effect by increasing the driving voltage of the anti-peeping element under low-temperature operation. Therefore, the anti-peeping module can exert a normal anti-peeping effect both in normal temperature and low-temperature environments.

[0093] In summary, although the present invention has been disclosed as above with embodiments, it is not intended to limit the present invention. Those of ordinary skill in the technical field to which the present invention pertains can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the scope of the appended patent application.

Claims

1. An anti-peeping module, characterized in that, Comprising: An anti-peeping element, including a liquid crystal layer, a first anti-peeping electrode layer, and a second anti-peeping electrode layer, wherein the liquid crystal layer is located between the first anti-peeping electrode layer and the second anti-peeping electrode layer; A temperature sensor for sensing an ambient temperature; A voltage adjustment circuit coupled to the temperature sensor; And A driving circuit coupled to the voltage adjustment circuit and the anti-peeping element; Wherein when the ambient temperature is a first ambient temperature and the anti-peeping element operates in an anti-peeping mode, the driving circuit outputs a first driving voltage to the anti-peeping element; when the ambient temperature is a second ambient temperature and the anti-peeping element operates in the anti-peeping mode, the driving circuit outputs a second driving voltage to the anti-peeping element, wherein the first ambient temperature is greater than the second ambient temperature, and the absolute value of the first driving voltage is less than the absolute value of the second driving voltage.

2. The anti-peeping module according to claim 1, wherein The first ambient temperature is greater than or equal to 0°C, and the second ambient temperature is less than 0°C.

3. The anti-peeping module according to claim 2, wherein The first ambient temperature is 25°C to 30°C, and the second ambient temperature is -40°C.

4. The anti-peeping module according to claim 1, wherein The absolute value of the second driving voltage is 1.4 to 2 times the absolute value of the first driving voltage.

5. The anti-peeping module according to claim 4, wherein The absolute value of the first driving voltage is 4 to 5V, and the absolute value of the second driving voltage is 7 to 8V.

6. The anti-peeping module according to claim 1, wherein The driving voltage is an alternating current signal, and the driving voltage is positive within a part of a cycle of the alternating current signal and negative within the remaining part of the cycle.

7. The anti-peeping module according to claim 1, wherein The temperature sensor includes a thermistor.

8. The anti-peeping module according to claim 1, wherein The anti-peeping element further includes a first alignment layer and a second alignment layer, the first alignment layer is located between the first anti-peeping electrode layer and the liquid crystal layer, and the second alignment layer is located between the second anti-peeping electrode layer and the liquid crystal layer.

9. An anti-peeping display device, characterized in that, Comprising: A display panel; And The anti-peeping module as claimed in claim 1; Wherein the anti-peeping element is located on the light-incident side or the light-emitting side of the display panel.

10. The anti-peeping display device according to claim 9, characterized in that, It further includes a backlight module, wherein the anti-peeping element is located between the display panel and the backlight module, or the display panel is located between the backlight module and the anti-peeping element.

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